Nov 29, 2017

Astronomers find 72 new galaxies deep in the universe

Hubble Ultra-Deep Field region observed through the Multi Unit Spectroscopic Explorer. Image: ESO / MUSE HUDF collaboration

Astronomers working with the Very Large Telescope in Chile have surveyed a patch of the sky and detected 72 new galaxies never seen before.

What's new: Beginning in 2004, the Hubble Space Telescope delivered detailed pictures of a patch of sky that now bears its name — the Hubble Ultra-Deep Field is a view nearly 13 billion years back into the early universe. Using the Multi Unit Spectroscopic Explorer (MUSE) instrument, researchers again looked at this well-studied region and found 72 new galaxies and collected more information about 1,600 of the estimated 10,000 galaxies there. (The existence of the new galaxies needs to be confirmed, possibly by the James Webb Space Telescope when it launches next year.)

How they did it: MUSE measures the amount of different colors of light in every pixel of an image, allowing it to detect properties of galaxies not seen before. Two findings from 10 papers published today in the journal Astronomy & Astrophysics:

  • The 72 candidate galaxies emit only one color of light called Lyman-alpha. It's unclear how these galaxies form but studying them will help to better understand how they created stars in the early universe.
  • They also observed halos of hydrogen gas around some of the galaxies that may help to explain how the ingredients for galaxies come together.

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Updated 10 mins ago - Politics & Policy

Trump threatens to "assume control" of Minneapolis over unrest

Flames from a nearby fire illuminate protesters standing on a barricade in front of the Third Police Precinct in Minneapolis on Thursday. Photo: Kerem Yucel/AFP via Getty Images

President Trump threatened via Twitter early Friday to send the national guard to Minneapolis following three days of massive demonstrations and unrest in the city over George Floyd, a black man who died in police custody this week.

Details: "I can’t stand back & watch this happen to a great American City, Minneapolis. A total lack of leadership. Either the very weak Radical Left Mayor, Jacob Frey, get his act together and bring the City under control, or I will send in the National Guard & get the job done right," Trump tweeted after a police station was torched by some protesters.

23 mins ago - Technology

Twitter: Trump's Minnesota tweet violated rules on violence

Twitter said Friday morning that a tweet from President Trump in which he threatened shooting in response to civil unrest in Minneapolis violated the company's rules. The company said it was leaving the tweet up in the public interest.

Why it matters: The move exacerbates tensions between Twitter and Trump over the company's authority to label or limit his speech and, conversely, the president's authority to dictate rules for a private company.

Updated 2 hours ago - Politics & Policy

In photos: Protests over George Floyd's death grip Minneapolis

Protesters cheer as the Third Police Precinct burns behind them on in Minneapolis on Thursday night. Photo: Stephen Maturen/Getty Images

Cheering protesters set a Minneapolis police station on fire Thursday night in the third night of unrest following the death of George Floyd, a black man who died in police custody in the city, per AP.

The state of play: Minnesota's governor on Thursday activated the state's national guard following violent outbreaks throughout the week, as the nation waits to see if the officers involved will be charged with murder.